If I had 1000 Denarius and went to Greece or any other more eastern location would they stop taking my currency, exchange it at a 1:(?) rate like we do in modern times, or simply would they give you your weight in what ever precious metal you had in flat local currency? How about a Lesser known currency then the romans? what was the standard practice of the time?
From what I've been able to dig up it seems to have been left up to the two traders to come to an agreement on currency exchange or they would just barter goods. A factor in this would be the country trade would happen in. Trade in Greece would often use greek currency for example.
Source: Mark Cartwright, “Trade in Ancient Greece,” Ancient History Encyclopedia, last modified January 18, 2012, http://www.ancient.eu /article/115/.